The present invention relates to an exhaust particulate removing filter of a Diesel engine using ceramic fibers.
In the conventional exhaust particulate removing filter of a Diesel engine, two felts formed of ceramic fibers are sandwiched between two wire nets for a heater, which is formed in a shape of bellows, and the resultant article is mounted on a metal frame.
Where a filter having the high collecting efficiency of exhaust particulates is fabricated, it is necessary to make a felt thick. However, in the filter in which the felt is thick, it is difficult to mount it on a metal frame, and it is necessary to change the shape of the metal frame and mounting parts onto the metal frame.
In the light of the aforementioned problem, it is an object of the present invention to provide an exhaust particulate removing filter of a Diesel engine in which even if a felt formed of ceramic fibers is made to be thick, a filter is mounted easily on a metal frame.
For solving the above-describe problem, the present invention provides an exhaust particulate removing filter of a Diesel engine characterized in that the width of at least one felt out of a plurality of felts formed of ceramic fibers superposed between two wire nets for a heater is made to be narrower than the width of said wire nets for heater, the width of other felts is made to be the same as the width of said wire nets for a heater, a superposed body of said wire nets for a heater and said felts is bended lengthwise to form a tube having a petal shape in section, and a metal frame is connected to the outer peripheral side of both ends of said tube.
In the exhaust particulate removing filter (hereinafter merely referred to as a filter) according to the present invention, a superposed body of two inner and outer wire nets for a heater over a plurality of felts formed of ceramic fibers is formed into a tube in the form of a bellows or a petal in section. Where a filter of which collecting efficiency is high, a single thick felt is not used but use is made of one in which a plurality of thin felts different in roughness of the meshes are superposed, only one or two felts are made to have the same width as the metal wire nets for a heater, and the remaining felts are made to be narrow in width so as not to come in contact with the wire net for a heater. In a filter comprising a tube formed from the wire nets for a heater and the felts, the thickness of both ends is thinner than the thickness of a central part, and even if the shape of the metal frame and the mounting parts onto the meal frame is not changed, mounting onto the metal frame is easy.
These and other objects and features of the invention will become more apparent upon a perusal of the following description taken in conjunction with the accompanying drawings wherein: